Self-expanding, pseudo-braided intravascular device

ABSTRACT

A self-expanding, pseudo-braided device embodying a high expansion ratio and flexibility as well as comformability and improved radial force. The pseudo-braided device is particularly suited for advancement through and deployment within highly tortuous and very distal vasculature. Various forms of the pseudo-braided device are adapted for the repair of aneurysms and stenoses as well as for use in thrombectomies and embolic protection therapy.

BACKGROUND OF THE INVENTION

[0001] The present invention relates to self-expanding, knitted devicesand more particularly, to a self-expanding knitted device forintravascular repair of distal and tortuous vasculature.

[0002] The vasculature of an animal or a human characteristicallysuffers from a variety of maladies. Vessel walls can weaken and becomedistended over time in response to blood flow and pressures, therebyresulting in formation of aneurysms. Such aneurysms can take on a myriadof forms. In particular, aneurysms may form at or near bifurcatedvessels creating enlarged areas about the bifurcation, or may form apocket, for example, in side walls of vessels. Due to the complicationsassociated with aneurysms that rupture or otherwise fail, it is criticalthat an aneurysm be treated expeditiously and effectively. Intravasculartreatment procedures include placing grafts within the aneurysm in amanner to ensure that blood flows through the graft rather than throughthe weakened vessel. Additionally, in the event that the aneurysm is inthe form of a pocket in the side wall of a vessel, a stent might firstbe placed at the repair site then the pocket filled with material suchas coils.

[0003] Stenoses also typically form in vasculature of humans andanimals. Specifically, thrombotic or atherotic stenoses can form nearlyanywhere in the vasculature. Such narrowing of the vessel is, of course,highly dangerous to the patient where the afflicted vessel provides thesole blood flow access to critical parts of the body. To treat suchstenoses, a supporting structure can be placed at the diseased site forthe purpose of enlarging and holding open the vessel. It is known in theart to employ stents for this purpose.

[0004] Vessel occlusions can also be treated by employing devices whichare actuated to debulk and remove vessel occluding thrombi. Thisprocedure is generally referred to as a thrombectomy. Typically, suchdevices are intravascularly advanced to the repair site and manipulatedto remove the unwanted material from the vessel by physically engagingthe thrombus and severing the same from the vessel wall.

[0005] Due to procedures such as thrombectomies or due to the natural,albeit undesirable, function of a patient's vasculature, emboli may befound traveling through a blood vessel. Embolic material can causeunwanted blockages or otherwise facilitate the formation of an occlusionin a vessel which too, can be highly dangerous to a patient. To addressthis problem, emboli-catching filters can be intravascularly placedwithin vasculature to thereby provide embolic protection. Such devicesare often implanted temporarily within vasculature and removed uponbeing satisfied that the undesirable embolic material has been captured.

[0006] In certain situations, it is desirable to aid the formation ofthrombus. For example, devices may be placed within aneurysmal spaces toslow and eventually cease blood flow therethrough. This procedure issometimes referred to as embolic therapy, the basic thrust of which isto minimize or eliminate exposure of weakened sections of vasculature toblood flow and pressure.

[0007] Unfortunately, many areas of vasculature are inaccessible by aconventional intravascular repair means because the repair devicestypically employed are often too large or rigid to be effectivelyadvanced through tortuous vasculature or to vasculature that is verydistal to the site through which the vasculature is accessed.Alternatively, in the event that there is success in advancing therepair devices to the diseased portion or repair site of thevasculature, conventional repair devices sometimes lack a large enoughexpansion ratio and/or radial stiffness to accomplish the necessaryrepair. Moreover, conventional devices can lack a profile suited toavoid traumatic engagement with a vessel wall or sufficient radiopacityso that remote observation is impossible.

[0008] Thus, where an intravascular approach is not available to thephysician, invasive surgical techniques must be applied. To wit, apatient's chest, abdomen or cranium, for example, must be directlytraversed in a major surgical procedure.

[0009] Hence, those concerned with repair of diseased vasculature haverecognized the need for devices that can be employed to effectivelyrepair distal and highly tortuous vasculature. The present inventionfulfills these needs.

SUMMARY OF THE INVENTION

[0010] Briefly, and in general terms, the present invention providesdevices contemplated for the repair of highly tortuous and distalvasculature. Basically, the invention is directed to a self-expanding,pseudo-braided structure that is characterized by having a largeexpansion ratio and high flexibility as well as an improved radialstrength accomplished through the advantageous utilization of deflectionenergy.

[0011] In one preferred embodiment, the devices of the present inventionare fabricated from a single filament configured into a repeatinghelical pattern that is interlaced into a mesh or pseudo-braided tubularshape. The filament may embody an elongate highly elastic and shapesettable material. A reversal of direction that the filament undergoespresents a blunt, rounded surface that is atraumatic to vessel walls.The structure in the present application is referred to aspseudo-braided. Braiding is the interlacing of at least three wires atvarious angles to each other to form a braid, whereas the presentinvention uses a single filament that is interlaced with itself alongthe length of the structure at various angles. It is within the scope ofthe invention to interlace another filament or a plurality of otherfilaments into the pseudo-braid formed by the single filament.

[0012] In another aspect of the invention, the pseudo-braided orinterlaced structure has a high expansion ratio with a low metal tospace ratio. A large expansion ratio is accomplished by the uniquesingle filament construction that provides additional springback forces.

[0013] In other aspects of the invention, there are various methods forterminating the filaments. Additionally, various methods arecontemplated for adjusting the radiopacity as well as the expansion andspring characteristics of the pseudo-braided devices. Various methodsare also contemplated for improving coverage of the pseudo-braideddevices and enhancing the anchoring of the same within distal andtortuous vasculature.

[0014] The self-expanding, pseudo-braided devices disclosed are intendedfor use in addressing various maladies effecting vasculature. Inparticular, the self-expanding, pseudo-braided devices can be configuredspecifically to facilitate the repair of aneurysms and stenoses as wellas to act as filter or thrombectomy devices.

[0015] These and other objects and advantages of the invention willbecome apparent from the following more detailed description, when takenin conjunction with the accompanying drawings of illustrativeembodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016]FIG. 1 is a side view of a pseudo-braided device of the presentinvention;

[0017]FIG. 2 is an end view of the pseudo-braided device shown in FIG.1;

[0018]FIG. 3 is a side view of a pseudo-braided device of the presentinvention, depicting a device with a flared end;

[0019]FIG. 4 depicts a first embodiment of a filament reversal;

[0020]FIG. 5 depicts a second embodiment of a filament reversal;

[0021]FIG. 6 depicts a third embodiment of a filament reversal;

[0022]FIG. 7 depicts a fourth embodiment of a filament reversal;

[0023]FIG. 8 depicts a fifth embodiment of a filament reversal;

[0024]FIG. 9 depicts a first embodiment of a method for joining ends ofa filament;

[0025]FIG. 10 depicts a second embodiment of a method for joining endsof a filament;

[0026]FIG. 11 depicts a third embodiment of a method for joining ends ofa filament;

[0027]FIG. 12 depicts a fourth embodiment of a method for joining endsof a filament;

[0028]FIG. 13 depicts a fifth embodiment of a method for joining ends ofa filament;

[0029]FIG. 14 depicts a sixth embodiment of a method for joining ends ofa filament;

[0030]FIG. 15 depicts a seventh embodiment of a method for joining endsof a filament;

[0031]FIG. 16 depicts a eighth embodiment of a method for joining endsof a filament;

[0032]FIG. 17 is a perspective view of a first alternative method offorming a pseudo-braided device of the present invention;

[0033]FIG. 18 is a perspective view of a second alternative method offorming a pseudo-braided device of the present invention;

[0034]FIG. 19 is a side view of a sectioned portion of a blood vesselsuffering from an aneurysm and a pseudo-braided device of the presentinvention being deployed from a catheter;

[0035]FIG. 20 depicts the implantation of the device of FIG. 19 within avessel;

[0036]FIG. 21 is a side view of a sectioned portion of a blood vesselsuffering from an aneurysm and a pseudo-braided device of the presentinvention being deployed from an alternative embodiment of a deliverycatheter;

[0037]FIG. 22 is a side view of a sectioned portion of a blood vesselsuffering from a stenosis and a pseudo-braided device of the presentinvention being deployed from a catheter;

[0038]FIG. 23 depicts the implantation of the pseudo-braided device ofFIG. 22 within a vessel;

[0039]FIG. 24 is a side view of a pseudo-braided device of the presentinvention configured as an embolic protection device;

[0040]FIG. 25 depicts a side view of an alternate embodiment of thepseudo-braided device of the present invention configured as an embolicprotection device;

[0041]FIG. 26 is a side view of a pseudo-braided device of the presentinvention configured as a thrombectomy device;

[0042]FIG. 27 depicts a side view of an alternate embodiment of thepseudo-braided device of the present invention configured as athrombectomy device;

[0043]FIG. 28 depicts a side view of yet another embodiment of thepseudo-braided device of the present invention configured as athrombectomy device; and

[0044]FIG. 29 is a side view of a sectional portion of a portion of ablood vessel suffering from an aneurysm and a pseudo-braided device ofthe present invention configured to be placed within the aneurysm.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0045] Turning now to the drawings, and particularly to FIGS. 1 and 2,there is shown a self-expanding pseudo-braided structure 50 of thepresent invention. The pseudo-braided device 50 is contemplated for usein highly tortuous and very distal vasculature of an animal or human.Due to its novel structure, the pseudo-braided device 50 is flexible ina compressed configuration and conformable to tortuous anatomy in arelaxed condition. Moreover, the device embodies high flexibility and alarge expansion capability while providing sufficient radial force(i.e., hoop stiffness).

[0046] In a presently preferred embodiment, the pseudo-braided device 50of the present invention is formed from the single filament 52. Thefilament 52 is configured into a repeating helical pattern that isinterlaced upon itself by passing the end of the filament over thenunder the filament forming the helix as the end of the filament is wounddown and back up the length of the structure to thereby form a generallytubular body 54. At the crossings of the filament there can be localdeformations formed as the top wire is bent over the bottom wire howeverit has been discovered that for most applications deformations are notnecessary to add spring force and resistance against fraying because ofthe ends formed by the reversal of winding. The tubular body 54 definesan interior lumen 56 and includes a first end 58 and second end 60.

[0047] It is also contemplated that the self-expanding pseudo-braidedstructure can embody modified tubular configurations. That is, as shownin FIG. 3, one end of the self-expanding pseudo-braided structure 50 caninclude an increased diameter section or flare 61. Alternatively, bothends of the device can include a flare 61, such flares can have the samegeneral shape or one flare may be greater than the other.

[0048] The filament 52 is preferably an elongate, highly elastic andshape settable member. In one preferred embodiment, the filament 52 hasa circular cross-sectional profile and can comprise nickel titaniumalloy, eligiloy™, steel or other suitable materials.

[0049] In order to assemble the pseudo-braided device 50, it iscontemplated that the filament 52 can be wrapped about a mandrel in afirst direction and in a helical fashion for a desired length along themandrel (not shown). Once the desired length is achieved, the directionof winding is reversed.

[0050] Reversal of winding can be accomplished in a number of ways. Itis contemplated, however, that the reversal of winding present a smooth,blunt surface that would be atraumatic to a vessel wall. As shown inFIG. 4, such an atraumatic reversal can be accomplished employing asimple arc 62. Atraumatic reversal can also be provided by single 64 ordouble 66 loop backs as well as a figure-8 reversal 68 or a full-turnhelical reversal 69 as shown in FIGS. 5-8, respectively.

[0051] Various radii of curvature and length of loops can be employedaccording to the application. The loops or hoops of the variousreversals contemplated can have a constant or irregular radii ofcurvature and the loops can have an acute radius of curvature (notshown). It is believed that minimizing stress concentrations in thereversals may have the added benefit of optimizing springback forces.Thus, stress concentration in the reversals can also be varied for aparticular application. Moreover, in order to facilitate the reversal ofdirection of the filament 52, the mandrel can have pegs extendingtherefrom at desired intervals, about which the filament can be routed.

[0052] Once a reversal direction is made, the filament is interlaced inan over/under fashion about itself in a helical pattern in the reverseaxial direction but same rotational direction. The desired density ofthe wall 70 defining the tubular body 54 is accomplished by altering thenumber of reversals and the longitudinal spacing 72 of adjacent memberswrapped in the helical pattern. That is, the number of traversals, whichis defined as the portion of the filament 52 between two reversals ofdirection, can be varied as can the number of revolutions per traversal.Typically, the number of reversals at each end 58, 60 of the tubularbody 70 number from six (6) to twelve (12) and as much as twenty (20).

[0053] Upon achieving a desired pseudo-braided pattern and wall density,the ends 74, 76 of the filament 52 are joined. There are a myriad ofways in which the ends 74, 76 can be joined. While the figuresillustrate such joining as occurring generally at the middle of thepseudo-braided device 50, it is also contemplated that such joining canoccur at the ends of the structure or anywhere in between. Ultimately,however, it is desired that the joining of the ends 74, 76 of thefilament 52 be accomplished in a manner such that the vessel wall ispresented with as atraumatic a surface as necessary for a particularapplication, there is a low profile, and no compromise in devicefunction.

[0054] As shown in FIGS. 9 and 10, one way of joining the end 74, 76 ofthe filament 52 is to twine them together. The ends 74, 76 of thefilament can also be joined by soldering or welding to form a weldedjoint 78 as shown in FIG. 11. A preferred method of welding is laserwelding.

[0055] Alternatively, the ends 74, 76 of the filament 52 can be joinedutilizing potted tantalum powder 80, as depicted in FIG. 12. In order todo so, the tantalum powder is first mixed with an epoxy. Thereafter, thefilament 50 is coated with the tantalum/epoxy compound and left to cure.

[0056] Moreover, the ends 74, 76 of the filament 52 can be configuredinto a linear slide arrangement 82 (see FIG. 13). In such anarrangement, one filament end 74 is wrapped around the other filamentend 76 which remains straight or undeformed. This means for joining theend 74, 76 of the filaments 52 has the advantage of compensating forlength mismatches. To wit, one wire can move relative to the other.

[0057] The ends 74, 76 of the filament can also be formed with flattenedwelding surfaces 84 (FIG. 14). These weld surfaces 84 are then alignedand thereafter welded together by conventional methods.

[0058] Finally, the ends 74, 76 of the filament 52 can be crimpedtogether using a sleeve 86 or are otherwise joined by way of a ballmember 88 (FIGS. 15 and 16). In both instances, a bore is provided toreceive both ends 74, 76 of the filament 52. In the case of the sleeve86 embodiment, the outer surface of the sleeve 86 can be crimped toretain the sleeve 86 on the ends 74, 76 of the filament 52. A press fitis contemplated for the ball 88 and configuration.

[0059] The assembled pseudo-braided device 50 embodies a number ofunique features. In particular, the reversal of the knit directionprovides a resilient response at the ends 58, 60 of the pseudo-braideddevice 50 compared to that of other conventional braided structures thathave unconnected wire ends. That is, reversals of direction act as aspring and tend to attempt to return to pseudo-braided device to itsoriginal expanded shape. This feature allows the pseudo-braided device50 to be compressed to smaller than ten (10) percent of its originaldiameter and once released, to spring back to its original uncompressedconfiguration. Accordingly, the pseudo-braided device 50 of the presentinvention is characterized by having a very large expansion ratio.

[0060] Embodying a very large expansion ratio provides thepseudo-braided device 50 of the present invention with a number ofadvantages. In particular, the pseudo-braided device 50 can be deliveredwithin vasculature using very small diameter catheters ormicrocatheters. This in turn allows for the placement of thepseudo-braided device 50 within very distal vasculature. Thus, usingmicrocatheters to deliver the pseudo-braided device 50 facilitatesadvancement through highly tortuous as well as very narrow vessels suchas in the cerebral vasculature.

[0061] Furthermore, the reversals of direction of the filament 50 tendto improve radial force (i.e., hoop stiffness) by forcing deflectionenergy to bend the reversal arc as well as displace the same. Withparticular reference to FIG. 4, reversals defined by simple bends 62embody relatively high stress concentrations at the bend 62. Such highstress concentrations may be suitable for a purpose requiring aparticular deflection energy. In contrast, reversals defined byfull-turn helixes (FIG. 8), for example, tend to distribute stressconcentrations throughout the helix 69 and therefore provide a differentdeflection energy. By comparison, braided devices that lack reversalsdeflect in response to a load much more readily than the ends 58, 60 ofthe pseudo-braided device of the present invention and those braideddevices only rely on pivots at the crossings of the wires whereas thepresent invention embodies crossings plus spring ends.

[0062] The crossing angle 90 can also be varied for a particularapplication. The crossing angle 90 is defined by two portions of thefilament that cross each other. It is presently contemplated that thecrossing angle can range up to approximately 90 degrees or more. It hasbeen found that the braid angle directly affects radial stiffness andconformability which can thus be optimized for a particular application.

[0063] It has also been recognized that joining the ends 74, 76 of thefilament maintains filament alignment. Filament alignment is importantparticularly when deploying the pseudo-braided device 50 in extremelytortuous vessels for a number of reasons. First, in the event thefilaments 52 were permitted to slide out of place, weaker areas would becreated in the pseudo-braided device 50. Those weaker areas would havean increased propensity to buckle. Secondly, if filaments 52 were toslide out of place, the mesh openings can become variable. As a result,there would be larger openings in the mesh or interlaced structure insome places that would reduce functionality of the device. Finally, iffilaments were permitted to slide out of place, catheter distortionduring deployment will likely increase. Thus, when the filaments 52 ofthe pseudo-braided device maintain good alignment while in thecompressed condition, the individual radial forces of each filament 52add together to form a consistent radial force in all directions alongthe length of the pseudo-braided device 50.

[0064] It is also possible to produce a pseudo-braided device 50 that iscomprised of one wire, where that one wire has variations along itslength that corresponds to specific pseudo-braiding processes of aparticular desired configuration. To wit, a wire could be masked andchemically etched to produce a variable diameter wire that correspondsto the pseudo-braided device 50 design of choice, such that for example,the bends of the filament 52 that comprise the ends of thepseudo-braided device 50 can be of a smaller diameter than the wire thatcomprises the remainder of the pseudo-braided device body 70.Additionally, the bends could be of a larger diameter for providing agreater expansion rate and radial force. These variations mayadvantageously create a pseudo-braided device 50 with a desiredstrength, without increasing its resistance to being pushed through acatheter lumen in a compressed configuration.

[0065] This kind of design variation could be followed for otherattributes as well. For example, such as for non-thrombogenic coatings,coatings laced with therapeutic drugs, plating processes to selectivelyincrease radiopacity, and plating processes to selectively increasestiffness.

[0066] Alternatively, rather than a round profile, the filament 52 canbe formed from a filament having various other cross-sectional profiles.That is, the filament can comprise an oval, triangular, rectangular,square, bowed, crescent moon, or tapered profiles. The filament 52itself can also be formed from a small diameter tube or be configuredinto a coil along its length.

[0067] It is also recognized that the desired pseudo-braided structurecan be made from a plurality of filaments 52. Such plurality offilaments 52 can be configured with a number of reversals of varyingtypes, so that the benefits associated therewith can be usedadvantageously. The ends of these filaments can also be joined togetherto provide atraumatic engagement with vessel walls as discussed above.

[0068] When deploying the pseudo-braided device 50 of the presentinvention within a patient's vasculature, it is desirable to be able toremotely observe the placement thereof. Thus, it is important that thepseudo-braided device 50 be sufficiently radiopaque so that such remoteobservation is possible by conventional methods such as fluoroscopy.

[0069] Referring now to FIGS. 15 and 16, the radiopacity of thepseudo-braided device 50 can be enhanced by employing platinum or othersufficiently radiopaque materials as the crimping sleeve 86 or the ballend 88. Platinum coils (not shown) could similarly be wrapped aboutportions of the filament 52 to act as radiopaque markers. Additionally,the filament 52 can be twined with one or more platinum filaments alongits length, thereby providing a pseudo-braided device 50 that isradiopaque from one end to the other.

[0070] Additionally, it is contemplated that in certain applications, itmay be desirable to plate the filament with gold or platinum. Theentirety of the tubular body 70 can be plated or the reversals could bemasked and the remainder of the body 70 be plated. By thus masking thereversals, the desirable spring characteristics of the pseudo-braideddevice 50 of the present invention can be preserved.

[0071] Referring now to FIGS. 17 and 18, there is shown methods ofmanufacturing the pseudo-braided device 50 of the present invention in amanner to optimize vessel coverage for particular applications. As shownin FIG. 17, a particular configuration of the pseudo-braided device 50can be formed by wrapping a filament 52 about a forming mandrel 92 suchthat there is tight winding at an inferior end portion 94 and relativelylooser winding at a superior end portion 96. The tightly wound portionbeing contemplated to provide the resultant pseudo-braided device 50with structure for anchoring and for increasing surface area for vesselcoverage. The more loosely wound portion provides a gradual transitionto the more tightly wound portion as well as a means for more easilydeploying the pseudo-braided device 50 when it is released from acatheter.

[0072]FIG. 18 additionally depicts a wavy midsection 98 which iscontemplated for use in also increasing coverage when the pseudo-braideddevice is deployed within a vessel. The waves can generally resemble asinusoidal path and can also take on an undulating serpentine pattern.Such waves 98 can alternatively extend the length of the filamentthereby providing the pseudo-braided device with increased coveragethroughout its length. Such waveforms are created by threading thefilament through a mesh setting shape then again wrapping the filamentabout a mandrel again setting the shape.

[0073] It has also been recognized that the waveforms like those shownin FIG. 18 can be spanned with a highly elastic material for the purposeof again improving coverage. As with the closely wound filamentembodiment, the waves can additionally improve anchoring capabilities byenhancing in a circumferential direction, the traction between thevessel wall and the pseudo-braided device 50.

[0074] The pseudo-braided device 50 of the present invention hasapplications in a number of areas including operating as an aneurysmcover, in conjunction with thrombotic and artherotic stenosis therapy,as an embolic protector, as a thrombectomy device and in embolictherapy. As stated, due to its high expansion ratio and superiorflexibility, the pseudo-braided device 50 can be placed withinvasculature and advanced deep within the patient's anatomy to a repairsite. Once there, the pseudo-braided device 50 can be deployed withinhighly tortuous vascular for the purpose of addressing the particularmalady effecting the vessel. As shown in FIGS. 19 and 20, thepseudo-braided device 50 of the present invention can be advanced withina blood vessel 100 using a delivery catheter 102. Due to the ability toreduce the pseudo-braided device 50 to less than 10 percent of theexpanded diameter, microcatheters can be utilized for this purpose. In apreferred embodiment, the delivery catheter is contemplated to includeor cooperate with a pusher 103 that operates to facilitate relativemovement between the pseudo-braided device 50 and the delivery catheter102.

[0075] In an alternate configuration (See FIG. 21), a compressed stenthas a lumen that a standard guidewire 201 can freely pass through. Thisallows improved access. When ready, the guidewire 201 can be withdrawnand replaced with the push wire 200 or the guidewire 201 can have aproximally placed pushing ring 202 that accomplishes the ejection of thepseudo-braided device from the delivery catheter 102.

[0076] Upon advancing the delivery catheter 102 to a repair site 104,the pseudo-braided device is deployed from a distal end 106 of thedelivery catheter 102 (FIG. 20). It is contemplated that any number ofconventional means may be employed to eject the pseudo-braided devicefrom the delivery catheter 102, including but not limited to a pusherdevice (not shown) configured coaxially within the delivery catheter 102which operates to engage a proximal end 58 of the pseudo-braided device50 while withdrawing the delivery catheter 102 proximally.

[0077] As stated, the pseudo-braided device 50 of the present inventionis also particularly suited to operate as an aneurysm cover. As shown inthe figures, the pseudo-braided device 50 can be deployed to overlay anopening 108 to an aneurysm 110 formed in a sidewall of a vessel. Bybeing so positioned, the pseudo-braided device 50 can redirect flow fromentering the aneurysm, become covered with endothelium cells and sealoff the opening into the aneurysm, or retain embolic coils 112 or otherthrombus producing materials inserted in the aneurysm sack 110. It is tobe noted that it is preferred to implace the pseudo-braided device 50prior to embolic material as the same prevents prolapse of material intothe parent vessel.

[0078] Using similar methods, the pseudo-braided device 50 of thepresent invention could additionally be employed to repair thrombotic orartherotic stenoses 14 found in a blood vessel 100 (See FIGS. 22 and23). Due to its high expansion ratio and enhanced radial strength (i.e.,hoop strength), the pseudo-braided device 50 can be deployed across thestenosis 114 and be allowed to self-expand to thereby press thethrombotic or artherotic material forming the stenoses against the wallsof the vessel 100. By doing so, the pseudo-braided device operates tohold open and enlarge the vessel 100 at the repair site.

[0079] By reconfiguring the basic structure of the pseudo-braided device50, as previously mentioned, the advantages provided by the presentinvention can be used to address other maladies effecting vessels. Morespecifically, the pseudo-braided device 50 can be reconfigured as anembolic protection device 120. With reference to FIGS. 24 and 25, asuperior end portion 122 of the contemplated embolic protection devicescan be necked down so as to form a generally conical profile. Suchnecking could be accomplished by way of altering the manufacturingprocess or the superior end 122 of the pseudo-braided structure cansimply be restrained to a relatively smaller cross-sectional profile byway of adhesion or mechanical devices. It is contemplated that thesuperior end 120 of the embolic protection device 120 be affixed byconventional means to an elongate member 124 that is positionable withina delivery catheter similar to that depicted in FIGS. 19-23. Theinferior end 126 of the embolic protection device 120, in its expandedform, provides a generally circular, cross-sectional profile, openingfor receiving blood flow.

[0080] In one embodiment of the embolic protection device 120 (FIG. 25),a plurality of proximally extending filaments or wire loops 128 arerouted about portions of the filament defining the inferior end 126 ofthe embolic protection device 120. Proximal ends 129 of the loops can beaffixed to a collar that is intended to slide along the elongate member124. Independent control of the collar is also contemplated such that aseparate actuator (not shown) which extends to the operator can besupplied to manipulate the position of the collar along the elongatemember 124. In either case, the loops 128 are provided in the eventadditional control of the opening and closing of the embolic protectiondevice 120 is desired.

[0081] Upon advancing the embolic protection device 122 to a desirablelocation within a patient's vasculature, the elongate member 124 is heldstationary while the delivery catheter (not shown) is withdrawnproximally. The inferior end portion 26 and a tubular midsection 130 ofthe embolic protection device 122 are then permitted to self-expandagainst the walls of the vessel into which the device is deployed. Thefully opened embolic protection device 120 permits blood to flow intoits interior and through its pseudo-braided walls but acts as a barrierto emboli passing through the blood. That is, emboli entering theembolic protection device 120 are captured by its pseudo-braidedstructure. The captured emboli can thereafter be removed from thepatient's vasculature when the embolic protection device 120 is removedor other conventional means such as suction devices can be employed toremove the emboli.

[0082] Turning now to FIGS. 26-28, there are shown various embodimentsof the present invention configured as thrombectomy devices 148. Suchthrombectomy devices 148 can be advanced and deployed within a patient'svasculature using the delivery catheter depicted in FIGS. 19-23. Withspecific reference to FIG. 26, the pseudo-braided device of the presentinvention can be attached at its ends 140, 142 by way of collars 144 toan elongate member 146 to thereby form one embodiment of a thrombectomydevice 148. Upon deployment and expansion within a target vessel, thethrombectomy device assembly 148 provides a mid-section 150 that iswell-suited for engaging and, upon rotation of the device, shearingthrombus from a vessel wall. In order to facilitate self-expansion, onecollar 144 is permitted to slide along the elongate member 146, whilethe other collar is longitudinally fixed thereto.

[0083] As shown in FIGS. 27 and 28, the thrombectomy devices 148 mayalso embody pseudo-braided portions of varied density. For example, themore densely pseudo-braided midsection 152 of the device depicted inFIG. 27 is particularly suited for accomplishing the thrombectomywhereas its less densely pseudo-braided superior end portion 154 isintended for capture of emboli. The thrombectomy device 148 of FIG. 28embodies a less densely pseudo-braided midsection contemplated formacerating a thrombus adhering to a blood vessel wall whereas itssuperior end portion 160, being more densely pseudo-braided, isconfigured for removal and capture of emboli.

[0084] The pseudo-braided device 50 of the present invention can also beclosed at each of its ends to form an expandable spherical shape that issuited as an embolic therapy device 170. With reference to FIG. 29, suchan embolic therapy device can be advanced within a vessel using adelivery catheter 102. The embolic therapy device 170 can then bedeployed within an aneurysm sack 110 and permitted to self-expand tothereby facilitate thrombus formation. A conventional releasableconnection 172 to an elongate delivery assembly sub-component 174 iscontemplated so that the embolic therapy device 170 can remain in theaneurysm 110 when the delivery assembly is removed from the patient.

[0085] In view of the foregoing, it is clear that the pseudo-braideddevice of the present invention is useful in numerous of applications.Moreover, due to its high expansion ratio and flexibility, thepseudo-braided device of the present invention can be employed to repairvery distal as well as tortuous portions of a patient's vasculature.

[0086] It will be apparent from the foregoing that, while particularforms of the invention have been illustrated and described, variousmodifications can be made without departing from the spirit and scope ofthe invention. Accordingly, it is not intended that the invention belimited, except as by the appended claims.

What is claimed is:
 1. A device comprising: an elongate filamentconfigured into a pseudo-braided pattern and formed to define agenerally tubular body with a first end and a second end; and said firstand second ends each being defined by a plurality of endless reversalsof direction of said filament.
 2. The device of claim 1, furthercomprising at least one more elongate filament interlaced in thepseudo-braided pattern.
 3. The device of claim 1, wherein said pluralityof endless reversals define a simple arc.
 4. The device of claim 3,wherein said simple arc has a variable radius of curvature.
 5. Thedevice of claim 3, wherein said simple arc has a uniform radius ofcurvature.
 6. The device of claim 1, wherein at least one of saidplurality of reversals embody loops having a generally constant radiusof curvature.
 7. The device of claim 1, wherein at least one of saidplurality of reversals embody loops having a variable radius ofcurvature.
 8. The device of claim 1, wherein at least one of saidplurality of reversals embody a full-turn helical configuration.
 9. Thedevice of claim 1, wherein said pseudo-braided pattern is uniform alonga length of said tubular body.
 10. The device of claim 1, wherein saidpseudo-braided pattern is non-uniform along a length of said tubularbody.
 11. The device of claim 1, wherein said filament is undulatedbetween crossing points.
 12. The device of claim 1, wherein saidfilament includes a first end and a second end, said first and secondends being joined together by twining.
 13. The device of claim 1,wherein said filament includes a first end and a second end, said firstand second ends being joined together by welding.
 14. The device ofclaim 1, wherein said filament includes a first end and a second end,said first and second ends being joined together by epoxy.
 15. Thedevice of claim 1, wherein said filament includes a first end and asecond end, said first and second ends being joined together by asleeve, said sleeve embodying radiopaque material.
 16. The device ofclaim 1, wherein said filament includes a first end and a second end,said first and second ends being joined together by a ball end, saidball end embodying radiopaque material.
 17. The device of claim 1,wherein said filament includes a first end and a second end, said firstand second ends being joined in a middle portion of the device.
 18. Thedevice of claim 1, wherein said filament includes a first end and asecond end, said first and second ends being joined at an end of thedevice.
 19. The device of claim 1, wherein said filament is made from atube.
 20. The device of claim 1, wherein said filament is configuredinto a coil.
 21. The device of claim 1, wherein said filament has avariable cross-sectional profile.
 22. The device of claim 1, whereinsaid plurality of endless reversals of direction function to enhancehoop strength of said device at said first and second ends thereof. 23.The device of claim 1, wherein said device can be reduced to less than10 percent of its expanded diameter.
 24. The device of claim 1, whereinsaid device can be delivered into a patient's vasculature by amicrocatheter.
 25. The device of claim 1, wherein said device isself-expanding.
 26. The device of claim 1, wherein at least one of saidfirst end and said second end is configured with a flared portion. 27.The device of claim 26, wherein each of said first and second ends areflared.
 28. A device for use in embolic protection, comprising: anelongate filament configured into a pseudo-braided pattern and formed todefine a body having a generally tubular inferior portion and agenerally conical superior portion; and said proximal and distalportions each being defined by a plurality of endless reversals ofdirection of said filament.
 29. The device of claim 28, furthercomprising: an elongate wire having proximal and distal end portions;and said body configured about said elongate wire, said generallyconical superior portion being affixed to said elongate wire.
 30. Thedevice of claim 29, further comprising a delivery catheter, saiddelivery catheter having a generally tubular portion that is adapted forreceiving said body and said elongate wire.
 31. The device of claim 29,further comprising a plurality of loops, a first end of said loopsengaging said inferior portion of said body and a second end of saidloops being affixed to said elongate wire.
 32. The device of claim 31,further comprising a collar, said collar being joined to said pluralityof loops.
 33. The device of claim 32, wherein said collar is configuredto slide longitudinally along said elongate wire.
 34. The device ofclaim 32, wherein said body is self-expanding.
 35. A thrombectomydevice, comprising: an elongate filament configured into apseudo-braided pattern and formed to define a body having a first endand a second end; and said first and second ends each being defined by aplurality of endless reversals of directions of said filament.
 36. Thedevice of claim 35, further comprising: an elongate wire, said bodybeing configured about said wire; and a collar configured about saidelongate wire in a slidable fashion, said collar affixed to first saidend of said body; wherein said second end of said body is affixed tosaid elongate wire.
 37. The device of claim 35, wherein saidpseudo-braided pattern is uniform along a length of said body.
 38. Thedevice of claim 35, wherein said pseudo-braided pattern is varied alonga length of said body.
 39. The device of claim 35, wherein said body isself-expanding.
 40. A device for use in embolic therapy, comprising: anelongate filament configured into a pseudo-braided pattern and formed todefine a generally spherical body; and a delivery microcatheterreleasably connected to said spherical body.
 41. The device of claim 40,wherein said spherical body is self-expanding.
 42. The device of claim40, wherein said spherical body is formed from a tube having first andsecond ends, said first and second ends being collapsed upon themselvesto thereby define a closed spherical structure.